Method for manufacturing fan rotor

ABSTRACT

An exemplary method for manufacturing a fan rotor includes the following steps. First, a discoid-shaped metal sheet is provided. Second, the metal sheet is stamped such that the stamped metal sheet includes a hub at a middle thereof, a blade-portion spaced from and surrounding the hub, and supporting bars interconnecting the hub and the blade-portion. The blade-portion includes outer peripheral blades adjacent to each other. Third, a free end of each blade is curled up by force applied along a direction substantially perpendicular to a plane of the blade-portion. Finally, each blade is bent downward about an axis coinciding with a portion of one side of the blade that connects with an inner periphery of the blade-portion.

BACKGROUND

1. Technical Field

The present disclosure relates to a method for manufacturing a fan rotor typically used in a fan of an electronic device.

2. Description of Related Art

With the continuing development of electronics technology, the operating speeds of processors, memory cards, etc. of electronic devices such as notebook computers have become faster. Therefore components such as processors generate much heat requiring removal. Heat dissipation apparatuses equipped with a fan are traditionally disposed in electronic devices to help transfer the heat from the processor to the outside of the electronic device. Thus a normal, stable operating temperature of the processor is maintained.

However, with the miniaturization of many electronic devices, in order to use space more effectively, a shape of the rotor of a conventional fan is quite complex. In addition, the fan rotor is normally manufactured by way of injection molding or a metal die-casting molding process. Due to limitations inherent in these manufacturing processes, a thickness of each blade of the fan rotor is relatively large. This restricts the complexity with which the fan rotor can be made, and restricts the degree to which the fan rotor can be miniaturized. Furthermore, the mold used in these manufacturing processes has a complex structure, and so the cost of fabricating the mold is great.

Therefore, a method for manufacturing a fan rotor which is capable of overcoming the above-described shortcomings is desired.

BRIEF DESCRIPTION OF THE DRAWINGS

Many aspects of the present disclosure can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, and certain one or more of the views are schematic; the emphasis instead being placed upon clearly illustrating the principles of the present disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.

FIGS. 1-5 respectively show aspects of different sequential stages in a process for manufacturing a fan rotor in accordance with a first embodiment of the present disclosure.

FIGS. 6-10 respectively show aspects of different sequential stages in a process for manufacturing a fan rotor in accordance with a second embodiment of the present disclosure.

DETAILED DESCRIPTION

Referring to FIG. 5, a method for manufacturing a fan rotor 1 in accordance with a first embodiment of the present disclosure includes multiple steps as described below.

As shown in FIG. 1, a metal sheet 10 is provided. A thickness of the metal sheet 10 is uniform, and the metal sheet 10 has high malleability. For example, the metal sheet 10 can be made of aluminum or copper. The metal sheet 10 is discoid.

As shown in FIG. 2, the metal sheet 10 is stamped into a modified discoid form. The modified metal sheet 10 includes a hub 11 at a middle thereof, a blade-portion 12 spaced from and surrounding the hub 11, and a plurality of supporting bars 13 interconnecting the hub 11 and the blade-portion 12. The blade-portion 12 is annular, and the hub 11 is round. The hub 11 is concentric with the blade-portion 12, and a center of the hub 11 is defined as a point O.

An outer periphery of the blade-portion 12 is cut by the stamping process to define a plurality of uniform blades 121, which are coplanar with each other. Each of the blades 121 includes a first long side 122, a second long side 123 opposite to the first long side 122, a first short side 124, and a second short side 125 opposite to the first short side 124. The first short side 124 of each blade 121 is positioned adjacent to the hub 11, and the second short side 125 is positioned remote from the hub 11. An outer end of each blade 121 is located more counterclockwise than an inner end of the blade 121. The first short side 124 of one blade 121 divides the second long side 123 of the left adjacent blade 121 into a first portion 1231 and a second portion 1232, with the first portion 1231 positioned generally adjacent to the hub 11, and the second portion 1232 positioned remote from the hub 11. In particular, the first long side 122, the first short side 124, the second short side 125, and the second portion 1232 of the second long side 123 of each blade 121 are cut by the stamping process such that they all have discrete edges. The first portion 1231 of the second long side 123 remains integrally connected with an inner periphery of the blade-portion 12 (even though the first portion 1231 is shown with a line in FIG. 2).

In this embodiment, the shapes and sizes of the blades 121 are uniform. An inner diameter of the blade-portion 12 is defined as r. A shortest distance between the point O and an extension line L of the first long side 122 of each blade 121 is constant, and is defined as d. The values of d and r meet the following relationship: 0<d<r.

As shown in FIG. 3, each blade 121 is curled up by force applied to a free end of the blade 121 (corresponding to the second short side 125), with the force being applied substantially along a direction perpendicular to a plane of the blade-portion 12.

As shown in FIG. 4, each blade 121 is then bent down along the first portion 1231 of the second long side 123. That is, each blade 121 is bent downward about an axis coinciding with the first portion 1231 of the second long side 123. In this embodiment, the total angle of the bending process is 90 degrees.

As shown in FIG. 5, when the above-described curling and bending processes are applied to all the blades 121, the fan rotor 1 is obtained.

Referring to FIG. 10, a method for manufacturing a fan rotor la in accordance with a second embodiment of the present disclosure includes multiple steps as described below.

As shown in FIG. 6, a metal sheet 20 is provided. A thickness of the metal sheet 20 is uniform, and the metal sheet 20 has high malleability. For example, the metal sheet 20 can be made of aluminum or copper. The metal sheet 20 is discoid.

As shown in FIG. 7, the metal sheet 20 is stamped into a modified discoid form. The modified metal sheet 20 includes a hub 21 at a middle thereof, a blade-portion 22 spaced from and surrounding the hub 21, and a plurality of supporting bars 23 interconnecting the hub 21 and the blade-portion 22. The blade-portion 22 is annular, and the hub 21 is round. The hub 21 is concentric with the blade-portion 22, and a center of the hub 21 is defined as a point O′. An outer periphery of the blade-portion 22 is cut by the stamping process to define a plurality of uniform blades 221, which are coplanar with each other. Each of the blades 221 includes a first long side 222, a second long side 223 opposite to the first long side 222, and a short side 224 interconnecting the first long side 222 and the second long side 223. The short side 224 of each blade 221 is positioned remote from the hub 21. An outer end of each blade 221 is located more counterclockwise than an inner end of the blade 221. The first long side 222, the short side 224, and the second long side 223 of each blade 221 are cut by the stamping process such that they all have discrete edges. In this embodiment, the shapes and sizes of the blades 221 are uniform. An inner diameter of the blade-portion 22 is defined as r. A shortest distance between the point O′ and an extension line L of the first long side 222 of each blade 221 is constant, and is defined as d. The values of d and r meet the following relationship: 0<d<r.

As shown in FIG. 8, each blade 221 is curled up by force applied to a free end of the blade 221 (corresponding to the short side 224), with the force being applied substantially along a direction perpendicular to a plane of the blade-portion 22.

As indicated in FIG. 9, each blade 221 is then twisted and stretched at an inner end thereof, such that an outer end thereof (corresponding to the short side 224) is substantially perpendicular to the plane of the blade-portion 22 and crosses the plane of the blade-portion 22. In other words, in this embodiment, the total maximum angle of the twisting process is 90 degrees.

As shown in FIG. 10, when the above-described curling, twisting and stretching processes are applied to all the blades 221, the fan rotor la is obtained.

In summary, for each of the above-described embodiments, the metal sheet 10, 20 is stamped to obtain a certain modified discoid shape. Then a curling process, and then a bending or a twisting/stretching process, are applied to the blades 121, 221 to form the final shape and position of the blades 121, 221. These methods circumvent the conventional need for fabricating molds, and thus can decrease the cost of mass producing fan rotors. Additionally, the thickness of each blade 121, 221 can be significantly less than that of blades of conventional fan rotors. Thereby, for any given electronic device having a particular amount of space available to accommodate a fan, the fan rotor 1, 1 a with the blades 121, 221 can provide more blades per unit volume. Thus, the heat dissipating performance provided by a fan employing the fan rotor 1, 1 a can be improved.

Even though aspects of particular embodiments are shown in the drawings and corresponding descriptions are provided herein, the entire disclosure is by way of illustration only. The principles and the features of the present disclosure may be employed in various and numerous embodiments thereof without departing from the scope of the disclosure. The above-described embodiments illustrate the scope of the disclosure but do not restrict the scope of the disclosure. 

What is claimed is:
 1. A method for manufacturing a fan rotor, comprising: providing a metal sheet; stamping the metal sheet, the stamped metal sheet comprising a hub at a middle thereof, a blade-portion spaced from and surrounding the hub, and a plurality of supporting bars interconnecting the hub and the blade-portion, an outer periphery of the blade-portion comprising a plurality of uniform blades arranged adjacently, the blades being coplanar with each other, each of the blades comprising a first long side, a second long side opposite to the first long side, a first short side, and a second short side opposite to the first short side, the first short side of each blade located near the hub, the second short side of each blade located remote from the hub, the first short side of a given one of the blades dividing the second long side of an adjacent one of the blades into a first portion and a second portion, the first portion located near the hub, the second portion located remote from the hub, and the first long side, the first short side, the second short side and the second portion of the second long side of each blade all having discrete edges; curling each blade upward by applying upward force to a free end of the blade; and bending each blade downward about an axis coinciding with the first portion of the second long side.
 2. The method of claim 1, wherein the blade-portion is annular, an inner diameter of the blade-portion is defined as r, a shortest distance between the center of the hub and an extension line of the first long side of each blade is constant, the shortest distance is defined as d, and the values of d and r meet the following relationship: 0<d<r.
 3. The method of claim 1, wherein a total angle of bending each blade relative to the first portion of the second long side is 90 degrees.
 4. The method of claim 1, wherein the metal sheet is malleable.
 5. The method of claim 1, wherein upon stamping the metal sheet an outer end of each blade is located more counterclockwise than an inner end of the blade.
 6. A method for manufacturing a fan rotor, comprising: providing a metal sheet; stamping the metal sheet, the stamped metal sheet comprising a hub at a middle thereof, a blade-portion spaced from and surrounding the hub, and a plurality of supporting bars interconnecting the hub and the blade-portion, an outer periphery of the blade-portion comprising a plurality of uniform blades arranged adjacently, the blades being coplanar with each other, each of the blades comprising a first long side, a second long side opposite to the first long side, and a short side interconnecting the first long side and the second long side, the short side of each blade located remote from the hub, the first long side, the short side and the second long side of each blade all having discrete edges; curling each blade upward by applying upward force to a free end of the blade; and twisting and stretching each blade at an inner end of the blade such that the short side of the blade is substantially perpendicular to a plane of the blade-portion.
 7. The method of claim 6, wherein the blade-portion is annular, an inner diameter of the blade-portion is defined as r, a shortest distance between the center of the hub and an extension line of the first long side of each blade is constant, the shortest distance is defined as d, and the values of d and r meet the following relationship: 0<d<r.
 8. The method of claim 6, wherein a total maximum angle of the twisting of each blade is 90 degrees.
 9. The method of claim 6, wherein the metal sheet is malleable.
 10. The method of claim 6, wherein upon stamping the metal sheet an outer end of each blade is located more counterclockwise than an inner end of the blade.
 11. A method for manufacturing a fan rotor, comprising: providing a metal sheet; stamping the metal sheet, the stamped metal sheet comprising a hub at a middle thereof, a blade-portion spaced from and surrounding the hub, and a plurality of supporting bars interconnecting the hub and the blade-portion, an outer periphery of the blade-portion comprising a plurality of uniform blades arranged adjacently, the blades being coplanar with each other, each of the blades comprising a first long side, a second long side opposite to the first long side, and a short side interconnecting the first long side and the second long side, the short side of each blade located remote from the hub, the first long side, the short side and the second long side of each blade all having discrete edges; curling each blade upward by applying upward force to a free end of the blade; and twisting and stretching each blade at an inner end of the blade such that the short side of the blade is substantially perpendicular to a plane of the blade-portion and crosses the plane of the blade-portion.
 12. The method of claim 11, wherein the blade-portion is annular, an inner diameter of the blade-portion is defined as r, a shortest distance between the center of the hub and an extension line of the first long side of each blade is constant, the shortest distance is defined as d, and the values of d and r meet the following relationship: 0<d<r.
 13. The method of claim 11, wherein a total maximum angle of the twisting of each blade is 90 degrees.
 14. The method of claim 11, wherein the metal sheet is malleable.
 15. The method of claim 11, wherein upon stamping the metal sheet an outer end of each blade is located more counterclockwise than an inner end of the blade. 